1. Field of the Invention
This invention concerns a drive unit and an electronic equipment which contains such a drive unit.
2. Description of the Related Art
Recently, the liquid crystal display is used for various electronic equipment such as a portable telephone, a personal haydyphone system (PHS), a cellular phone, a pager, a printer, an electronic notebook, a television and a personal computer as a small display device of low power consumption. It is desired for the liquid crystal display to be further reduced in power consumption and size. Therefore, it is also demanded for a liquid crystal drive unit included in this liquid crystal display device to be reduced in power consumption and scale.
In general, a lot of wiring connects the liquid crystal drive unit with a liquid crystal display panel. Therefore, there is raised a problem in that the above-mentioned wiring may become very complex depending on a direction of the drive unit relative to the display screen of the display panel. A technique which solves such a problem is disclosed in Japanese Patent Application Laid-Open No. Hei 7-152339, for example. In this disclosure, an address generating procedure for an access to a display RAM which stores code data is stored in a nonvolatile display control ROM. However, this technique needs a display control ROM having the same memory capacity as the display RAM. Since an area necessary for this display control ROM is very large, the liquid crystal drive unit will be increased in scale. Moreover, it is necessary to arrange all transistors composing the display control ROM in one unit on a semiconductor chip. Therefore, this technique using the display control ROM has a limited freedom of layout.